View Full Version : Controlling O2, MAP, timing ... with a Laptop ?

Roland Jacques
08-28-2008, 08:35 PM
I' been trying to detremine which controll system to buy.

I've heard of programs that allow you to hook up a Laptop to your Autos CPU. It seems ( not sure) that it would allow me to control O2 sensor, MAP, MAF, And Ignition timing! Is this a good idea!

Ive not heard of any other way of controlling your Ign timing. it seems to me that retarding the timing when Using HHO would be helpful in obtaining max HHO boosting performance.

08-29-2008, 09:40 AM
It's a viable possibility if you're up to the challenge. There's a very steep learning curve associated with EFI tuning, and it'll take a lot of reading and trial-and-error work to get everything right. If you just dive into it and start playing with the PCM calibrationo you'll quickly find that every change you make will impact multiple areas of the cars driveability. If youu already have a goood working knowledge of EFI systems and engine operation, go for it. If not, you're far better off building an HHO system and then taking the car to a professional for tuning.

FWIW, a tuning program doesn't let you control the actual sensor values, it just lets you change how the computer uses and responds to those values.

Roland Jacques
08-29-2008, 09:55 AM
I assume the fuel injection would not need to be changed. but i would think that the Ignition (spark) timing should be retarded to prevent early detination when using HHO.

Will a "tuning shop" be able to change the Spark timming to find the sweet spot with this new fuel?

08-29-2008, 05:12 PM
If you use only a small amount of HHO you likely won't need either. If you run a fairly high HHO output you will probably run into fuel metering problems before you run into timing issues. Modern injection systems monitor the O2 content of the exhaust and using HHO can throw these readings off and actually cause the engine to run too rich, neutralizing your gains. This is where the EFI tuning comes into play. The fuel maps and fuel trim feedback settings will need to be modified to get the air/fuel ratios right for max efficiency without sacrificing driveablility, and the timing may or may not need to be changed as well.

Yes, a good tuner can change the spark tables just as easily as he can the fuel tables.